Stephen Asma discusses his book On Monsters: An Unnatural History of Our Worst Fears. Just in time for Halloween, Asma talks about the monsters that have terrified people from ancient times up through today. A professor of philosophy at Columbia College Chicago, Asma is the author of many books, including Why I Am a Buddhist, Stuffed Animals and Pickled Heads: The Culture and Evolution of Natural History Museums and The Gods Drink Whiskey. He is also a guitarist, performing in the acoustic swing quartet Doctor Swing.